Numerous structures are known for coupling devices of this type.
One such coupling device generally comprises a tubular body having an internal channel axially subdivided into a first section arranged to receive in leaktight manner an end of a pipe secured to one of the elements that are to be connected together, and a second section having an endpiece fitted therein which is arranged to enable a coupling to be made subsequently to the other element for connection. Between these two sections of the internal channel, the body generally includes an internal shoulder forming a valve seat arranged to co-operate with a valve slide mounted in the internal channel beside the endpiece so as to slide between a closed position in which the valve slide is pressed in leaktight manner against the valve seat, and an open position in which the valve slide is spaced apart from the valve seat so as to define a passage for the fluid. A spring is conventionally interposed between the valve slide and the endpiece to urge the endpiece into its closed position against the valve seat. The manufacture of such coupling devices raises problems, in particular concerning making the valve seat and also assembling the valve which is done by putting successively into place in the body: the valve slide, the return spring, and the endpiece, and which requires handling that is relatively slow and awkward.
In order to facilitate assembly operations, it is known to make subassemblies that incorporate the valve slide, the return spring, and the valve seat. Assembly is then performed by initially inserting the subassembly into the internal channel of the body, and then inserting the endpiece which serves to secure the subassembly definitively in the body.